1. Field of the Invention
The present invention relates to a command input apparatus for computer equipment. More specifically, the invention relates to a command input apparatus which can be adapted to inputting commands provided in advance in an application program to be processed by the computer equipment.
2. Description of the Prior Art
Application programs to be executed by computer equipment, such as a program for preparing sentences, a program for preparing tables, or a program for data bases, have a variety of commands as well as functions for executing the commands. So far, the commands are inputted by a method by which command names assigned to each of the commands are inputted or by a menu selection method by which display data that represents the commands are displayed on a display screen so that the operator can select the desired command. In executing the above-mentioned application, programs, in particular, the menu selection method is generally used. In relatively small computer equipment, such as those that are generally called personal computer, business computer and the like, the keyboard, which is an input device, is provided with four, eight or sixteen keys of the type called function keys.
In an application program developed for computer equipment of this type, in particular, commands are assigned to each of the function keys, and the operator depresses a function key that corresponds to his work to execute and designate a predetermined command.
In recent years, the application programs have been prepared in which a variety of functions are combined together; i.e., each application program has been prepared with increased functions to cope with a high degree of work. Therefore, the above-mentioned function keys are no capable of handling all the functions. Increasing in the number of function keys, however, causes the keyboard to become bulky and further presents a problem from the standpoint of operation. So far, therefore, a structure has been employed in which the menu is stratified. That is, a number of functions are grouped being stratified into similar functional units, and a predetermined function in each stratum is selected thereby to select the predetermined function. An example is shown in FIG. 18 which explains a functional structure in an application program that has a function of preparing documents. Here, symbols F1, F2, F3, -----, F16 denote function keys arranged on the keyboard, which can be depressed. In preparing a document, here, the operator may wish to execute the "erase" operation. For this purpose, the operator, first, depresses a function key F2 to select an edit function and then depresses a function key F14, thereby to execute the desired erase function. After the processing is finished by this function, he may then execute the "document registration" operation. For this purpose, the procedure is first returned to the main menu. A function key F5 is depressed and then a function key F10 is depressed to carry out the "document registration" operation.
Prior art of this sort has been disclosed in Japanese Patent Laid-Open Nos. 5320/1985, 180622/1984, 5323/1985 and in Japanese Utility Model Laid-Open No. 126333/1984.
According to the conventional art in which the menu is stratified, more functions can be selected with fewer function keys, presenting a great advantage. Depending upon the type of application program, however, the number of commands increases with the increase in the number of functions, eventually causing the number of strata to increase. This means that an increased number of selections are required to select desired functions, presenting a problem from the standpoint of operation.
Thus, the application program for providing higher functions inevitably requires an increased number of commands. This is to make the apparatus feasible for a wide range of businesses. In practice, however, the operator does not equally use all of the functions of the application program. That is, depending upon the business in which the operator takes part, only a limited number of commands are frequently used. In order to input a limited number of commands, therefore, the operator must carry out laborious work to select desired commands, which in turn impairs the operability.